Add test of model/sort-preserving functionality.

glue/viewers/table/qt/tests/test_data_viewer.py

@@ -549,3 +549,65 @@ def test_table_with_dask_column():
     colors = ['#aa0000', '#aa0000', '#aa0000', None, None]
 
     check_values_and_color(model, data, colors)
+
+
+def test_table_preserve_model_after_selection():
+
+    # Regression test for a bug that caused table viewers to return
+    # to default sorting after a new subset was created with the row
+    # selection tool. This occurred because the model was reset.
+
+    app = get_qapp()  # noqa
+
+    d = Data(a=[1, 2, 3, 4, 5],
+             b=[3.2, 1.2, 4.5, 3.3, 2.2],
+             c=['e', 'b', 'c', 'a', 'f'], label='test')
+
+    dc = DataCollection([d])
+
+    gapp = GlueApplication(dc)
+
+    viewer = gapp.new_data_viewer(TableViewer)
+    viewer.add_data(d)
+
+    model = viewer.ui.table.model()
+
+    model.sort(1, Qt.AscendingOrder)
+
+    data = {'a': [2, 5, 1, 4, 3],
+            'b': [1.2, 2.2, 3.2, 3.3, 4.5],
+            'c': ['b', 'f', 'e', 'a', 'c']}
+    colors = [None for _ in range(5)]
+
+    check_values_and_color(model, data, colors)
+
+    # Create a new subset using the row selection tool
+
+    subset_mode = gapp._session.edit_subset_mode
+    subset_mode.edit_subset = None
+    viewer.toolbar.actions['table:rowselect'].toggle()
+
+    def press_key(key):
+        event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress, key, Qt.NoModifier)
+        app.postEvent(viewer.ui.table, event)
+        app.processEvents()
+
+    # Select the second row
+    press_key(Qt.Key_Tab)
+    press_key(Qt.Key_Down)
+    press_key(Qt.Key_Enter)
+
+    process_events()
+
+    # Check that the table model is still the same, which it
+    # should be since we aren't changing the viewer Data
+
+    post_model = viewer.ui.table.model()
+    assert post_model == model
+
+    # Check that the order is still the same
+
+    color = d.subsets[0].style.color
+    colors[1] = color
+
+    check_values_and_color(post_model, data, colors)